Thank you Allan! Low light shooting with the 5s is much better than with the 4s, but the sensor provides better defined images also in full light. Other two bonuses for photographers are: burst mode (if you shoot at moving subjtects ten photos per second are really good) and improved battery life. Are you considering to upgrade ?

I have a year left on my phone contract and I imagine that there will be new, even more shiny, phone out by then. I really like taking photos in low light and have been challenged by the capability of the iPhone 4/5 sensors. Perhaps some more time spent with the Slow Shutter app will yield better results for now.

I just tried with good results Night Cap, that enabled me to shoot in very low light conditions, where Slow Shutter would not be enough.
It is a bit crash-prone, but it manages decently focus even when light is not enough.
See my last post Sweet is the night as a good example of this.